If the third film in the Harry Potter series, last year's "Prisoner of Azkaban", seemed frightening with its soul-sucking Dementors and its German expressionist aesthetic, then the fourth installment, Harry Potter and the Goblet of Fire, will have kids quaking in their seats - and perhaps wishing they had an invisibility cloak to hide beneath.

This "Potter" earns its PG-13 rating - a first for the previously PG series about the boy wizard - as Harry grows into adolescence and learns more about his powers and his past. Of course, young fans have already devoured the J.K. Rowling books that provide the basis for the films, so they know what's coming. (The author is up to No. 6 out of seven planned.) But reading it on the page and seeing it on the screen can be two entirely different experiences, and several scenes will be disturbing to viewers regardless of age.

"Goblet of Fire" features the return of the dreaded Lord Voldemort - He-Who-Must-Not-Be-Named - the dark warlock who killed Harry's parents and tried to kill him, too, when he was just an infant. (Having survived the attack is what gives Harry a certain mystique among his professors and classmates at the Hogwarts School of Witchcraft and Wizardry; it also gave him his trademark lightning-bolt scar on his forehead.)